/*
 * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package com.itsaky.androidide.plugins.properties.parser;

import com.itsaky.androidide.plugins.properties.parser.MessageType.CompoundType;
import com.itsaky.androidide.plugins.properties.parser.MessageType.OrType;
import com.itsaky.androidide.plugins.properties.parser.MessageType.SimpleType;
import com.itsaky.androidide.plugins.properties.parser.MessageType.UnionType;
import java.util.ArrayList;
import java.util.List;

/**
 * An object to represent the comment that may precede the property specification in a Message. The
 * comment is modelled as a list of fields, where the fields correspond to the placeholder values
 * (e.g. {0}, {1}, etc) within the message value.
 */
public final class MessageInfo {

  /**
   * Dummy message info to be used when no resource key comment is available.
   */
  static final MessageInfo dummyInfo = new MessageInfo(null);
  /**
   * The fields of the Info object.
   */
  List<MessageType> types = new ArrayList<>();

  MessageInfo(String text) throws IllegalArgumentException {
    if (text != null) {
        if (!text.startsWith("# ")) {
            throw new IllegalArgumentException();
        }
      String[] segs = text.substring(2).split(", ");
      types = new ArrayList<>();
      for (String seg : segs) {
        types.add(parseType(seg));
      }
    }
  }

  public List<MessageType> getTypes() {
    return types;
  }

  boolean isEmpty() {
    return types.isEmpty();
  }

  @Override
  public String toString() {
    return types.toString();
  }

  /**
   * Split the type comment into multiple alternatives (separated by 'or') - then parse each of them
   * individually and form an 'or' type.
   */
  MessageType parseType(String text) {
    int commentStart = text.indexOf("(");
    if (commentStart != -1) {
      //remove optional comment
      text = text.substring(0, commentStart);
    }
    text = text.substring(text.indexOf(": ") + 2);
    String[] alternatives = text.split(" " + OrType.OR_NAME + " ");
    MessageType[] types = new MessageType[alternatives.length];
    for (int i = 0; i < alternatives.length; i++) {
      types[i] = parseAlternative(alternatives[i].trim());
    }
    return types.length > 1 ?
        new OrType(types) : types[0];
  }

  /**
   * Parse a subset of the type comment; valid matches are simple types, compound types, union types
   * and custom types.
   */
  MessageType parseAlternative(String text) {
    //try with custom types
    if (text.charAt(0) == '\'') {
      int end = text.indexOf('\'', 1);
      return new MessageType.CustomType(text.substring(1, end));
    }
    //try with simple types
    for (SimpleType st : SimpleType.values()) {
      if (text.equals(st.kindName())) {
        return st;
      }
    }
    //try with compound types
    for (CompoundType.Kind ck : CompoundType.Kind.values()) {
      if (text.startsWith(ck.kindName)) {
        MessageType elemtype = parseAlternative(text.substring(ck.kindName.length() + 1).trim());
        return new CompoundType(ck, elemtype);
      }
    }
    //try with union types
    for (UnionType.Kind uk : UnionType.Kind.values()) {
      if (text.startsWith(uk.kindName)) {
        return new UnionType(uk);
      }
    }
    //no match - report a warning
    System.err.println("WARNING - unrecognized type: " + text);
    return SimpleType.UNKNOWN;
  }
}
